Choosing what fertilizer to buy for your indoor plant can seem like a daunting task, but don’t worry, it’s really not all that complicated. I’m here to guide you through the steps in how to choose which one will work best for you. I do recommend reading “4 Things To Know BEFORE Fertilizing Your Indoor Plant” before you read any further.
NPK – The 3 Big Nutrients in Your Fertilizer
First off, you need to know that fertilizers are categorized by three numbers, NPK, which refer to the percentage of active ingredients of N (nitrogen), P (phosphorous), and K (potassium). They will always be listed in that order and different plants have varying needs of each nutrient.
Nitrogen helps with the “green-ness” factor of your plant and the growth of it’s leaves.
Phosphorus helps root and flower development and can be particularly important for flowering indoor plants such as orchids.
Potassium helps general cellular functions such as regulating the stomatas and catalyzing the plants enzymes.
Consider Specialized Fertilizers
If you have a flowering indoor plant or an indoor plant that is a bit more delicate, consider getting it a specialized fertilizer rather than just using an all-purpose one. They contain the nutrients needed for these plants to flower and do the best they can. If you are looking to fertilize an orchid, azalea, or poinsettia, I’d especially recommend looking into one of the fertilizers listed below.
Orchid Fertilizer | Azalea Fertilizer | Poinsettia Fertilizer |
All-Purpose Fertilizers
In general, your houseplant will do just fine with an all-purpose fertilizer about every month in spring and summer months. Some fertilizers are liquid and are directly added to water while others are powder and can be dissolved in your water. Either one works great for your indoor plants.
I recommend using a fertilizer with an NPK of 20-20-20, 10-15-10, or a 15-30-15. Professionals will often use a specialized 24-8-16 but an all purpose fertilizer will serve you and your indoor plants just fine. Any general brand should work just fine but below I’ve linked the fertilizers I’ve personally used and can recommend confidently.
Jack’s Classic All Purpose Fertilizer 20-20-20 Schultz Plant Food 10-15-10 This fertilizer is in powder form and is added directly into water to be dissolved. Mine has lasted a long time and is also great quality when it comes to fertilizers. This is a liquid fertilizer that you drop directly into your water. This one has also lasted me SUCH a long time and is quick and easy whenever I’m watering and remember that my plants need a quick fertilizer round.
And that’s it! Fertilizer can help with plant health and optimum growth though it’s not always necessary. Although, I do highly recommend being strict about fertilizing if you have a palm due to their slower vascular systems.
I hope this helps you when it comes to fertilizing your plant! If you want to hear more, check out our podcast “Plant School”, or our Tenney Plants YouTube Channel for specific guides on fertilizing your houseplant.